While I don't really disagree with you on what you have stated here, but I do think there were some very good, non-FW 190 radial installations prior to 1942. Certainly one was the Hughes H-1 which was nearly, according to my estimate, 100 mph faster at sea level than the only slightly bigger and heavier, but more powerful, Bf-109D. Now it was indeed a superb aerodynamically designed hand built aircraft with much effort in detail to reduce drag, but it had to have a very efficient engine housing. Also, I suspect a lot of engineering went into the nacelle design of the B-26 since speed was paramount. Lastly, the F4U which flew in 1940 was quite comparable to the Fw-190 in performance and was MUCH heavier and had a comparatively huge wing (60% larger). I do not believe there was much improvement in the engine installation as the F4U performance increase significantly, although I could be wrong. I think the significant increases in hp post 1942 made smaller items in drag reduction such as elliptical wings and mid mounted wings, and possible radial engine installation of minor importance.